Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the burden of disclosing side effects. It mentions a HEAD request and 'status only' but does not explicitly state that it is read-only, nor does it mention potential errors, rate limits, or network behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, succinct sentence that conveys the core action and output. There is no fluff or unnecessary detail, making it highly efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description is incomplete given the schema's many irrelevant parameters and lack of an output schema. It does not explain why parameters like 'zone' or 'path' exist, nor does it specify that only 'url' is relevant, leaving the agent potentially confused about usage.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema covers 100% of parameters with descriptions, but many parameters (e.g., 'city', 'feed', 'json') are irrelevant to the stated purpose of checking a URL status. The tool description adds no clarification on which parameters are actually used or how they relate to the operation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool performs a HEAD request on a public URL and returns only the status. It distinguishes itself from sibling tools like web-fetch or browser-url-ok by emphasizing 'status only'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description does not provide any guidance on when to use this tool versus alternatives such as web-fetch or playwright-url-ok. It is unclear whether this is preferred for quick status checks or if other tools should handle different scenarios.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.